Mortgage Payoff Calculator United States
This mortgage payoff calculator shows how extra monthly payments clear your US mortgage sooner, and the months and interest you save.
What it does
The Mortgage Payoff Calculator shows how adding a fixed extra amount to your monthly mortgage payment shortens the loan and reduces the total interest you pay. Enter your current balance, rate, remaining term and the extra you can afford to see the months saved and the interest saved.
Data sources & parameters
This calculator uses standard financial formulas and runs entirely in your browser. It needs no external rate data — your result is computed only from the values you enter above.
We always strive to use the latest data for every variable so our results and reports are as accurate as possible. Even so, errors are possible — you should not rely on this tool or its report alone, and we accept no liability for any decision made based on it.
The formula
monthly = balance × i ÷ (1 − (1 + i)^−n), where i is the monthly rate; then each month the balance grows by interest and falls by (monthly + extra) until it reaches zero
How it works
It first works out the standard principal-and-interest payment for your loan as it stands, then simulates the loan month by month with your extra payment added on top, clearing the balance faster and counting the months and interest along the way.
Where it is used
- Deciding whether rounding up your payment is worth it
- Comparing different extra-payment amounts before committing
- Estimating how many years earlier you could be mortgage-free
Worked example
Paying an extra $200.00 a month on a $300,000.00 balance clears the loan … months early and saves … in interest.
Paying a little extra on your mortgage each month can save a lot of interest over the life of the loan. Enter your current balance, interest rate, months left and the extra amount you can add each month, and this calculator shows how many months earlier the loan will be paid off and how much interest you save.
How extra payments shorten a mortgage
A fixed-rate mortgage has a level monthly payment that covers interest first and then reduces principal. Early on, most of each payment is interest because the balance is large. An extra amount on top of the required payment goes entirely to principal. That lowers next month's interest charge, so more of your regular payment goes to principal too. The effect builds every month, and the loan ends well before its scheduled term.
What the calculator does
First it works out the standard principal-and-interest payment from your balance, monthly rate and months remaining, and the interest you would pay by making only that payment to the end. Then it runs the loan month by month with your extra payment added, until the balance reaches zero. The difference between the two is the months and interest saved.
Reading the results
The headline is the months saved compared with paying only the required amount. The new payoff time is the total number of months to clear the loan. The interest saved compares total interest on the original schedule with total interest including the extra payment, and the chart shows the two totals side by side.
A worked example
Take a $300,000 balance at 6.5 percent with 360 months left. The required payment is about $1,896 a month, and paying only that means about $382,600 of interest over 30 years. Adding $200 a month pays the loan off in 277 months, 83 months early, and cuts total interest to about $279,200, a saving of about $103,400. Try other extra amounts to see how the months and interest saved change.
Deciding how much extra to pay
Some people round their payment up to the next hundred dollars, others add a fixed $100 or $200, and some make one extra payment a year by spreading it over the other months. You can test any of these by changing the extra monthly figure. Before committing, consider building an emergency fund, clearing higher-interest debt such as credit cards and getting any employer retirement match. Prepaying earns a guaranteed return equal to your mortgage rate, but the money is hard to get back, so keep enough cash for emergencies.
Assumptions and limitations
This is a planning estimate, not a loan quote. It assumes a fixed rate for the remaining term and the same extra payment every month. It does not model adjustable-rate resets, escrow for taxes and insurance, private mortgage insurance dropping off as equity grows, or one-off lump-sum payments. It assumes your servicer applies every extra dollar to principal in the month you pay it. Real loans can differ slightly in rounding and daily interest accrual. For a large prepayment or a refinance, confirm the details with your lender.
About This Mortgage Payoff Calculator
Use this mortgage payoff calculator to get an instant estimate based on the figures you enter. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.
Frequently asked questions
How does paying extra each month pay off a mortgage faster?
How much interest can extra payments actually save?
Is it better to pay extra on the mortgage or invest the money?
Will my lender let me make extra principal payments?
Does this calculator change my required monthly payment?
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